Method and means for attaching teeth and the like to the maxillar bone



June 4, 1968 J. SCIALOM 3,386,169

METHOD AND MEANS FOR ATTACHING TEETH AND THE LIKE TO THE MAXILLAR BONE Filed Jan. 2 Sheets-Sheet l 3N VEN TOR 3 C A ps I BY: film-hazel Sirzkev;

A Ti ORNE Y June 4, 1968 J. SCIALO 3,336,169

METHOD AND NS FOR ATTACH G TEETH AND THE LI E TO THE MAXILLAR BONE Filed Jan. 22, 1965 2 SheetsSheet 2 NVEN TOR JACQUES SC/ALUM By Maine) 5. girl f i TTORNEY United States Patent 3,386,169 METHfiD AND MEANS FOR ATTACHZNG TEETH AND THE LIKE T0 THE MAXILLAR BONE Jacques Scialcm, 52 Quai du Petit Pare, Saint Maur, Val-de-Marne, France Filed Jan. 22, 1963, Ser. No. 253,113 Claims priority, application France, Jan. 26, 1962, 886,988; Mar. 2, 1962, 889,782 16 Claims. (Cl. 32-40) The task of attaching artificial teeth or dental prostheses to the maxillary bone or of fixing loose teeth therein has met up to now with considerable difiiculties. Conventionally, two different methods are in use; according to a first known method a perforated support plate is mounted next to the bone and below the periosteum, said plates being provided with studs projecting beyond the tips of the gums and serving for carrying or supporting a tooth or a dental prosthesis which may be removable or nonremovable. The second method consists in inserting a support member into the bone itself. In the last-mentioned case the support member consists generally in an anchoring head and an extension which is threaded or of helicoidal form and of a comparatively large diameter of the order of 4 to 5 mm. These extensions cannot be introduced into the bone except in vertical direction. On account of their comparatively large diameter it is impossible to insert these support members in an inclined direction because this would entail the risk that they would reach into delicate interior portions (the maxillary sinus or the dental canal of the lower jaw bone) or they may even penetrate toward the outside and reach the mucous membrane. In addition, due to their necessary vertical position the length thereof is limited due to the presence of the maxillary sinus or of the dental canal. In any case the operation of putting such supports in place is rather delicate and may lead easily to effractions or bone breakage of suflicient magnitude so as to cause a serious damage. Moreover, since the inner bone structures retain a certain mobility one is bound, for attaching dental prostheses, to interconnect a plurality of said inserted support members by means of connecting bars.

It is therefore one of the objects of this invention to provide for a method and means which permit the attachment of artificial teeth or dental prostheses to the maxillary bone or to fix loose teeth therein without the difiiculties and dangers encountered in the conventional methods.

It is another object of this invention to provide for means of attachment or dental anchoring rods which can be inserted into the maxillary bone and are themselves of very simple construction.

With above objects in view the invention includes a method of attaching tooth means with the aid of anchoring post means to a maxillary bone, comprising the steps of drilling substantially from the center of the surface area of the maxillary bone where the tooth means is to be attached at least one channel of predetermined diameter into the maxillary bone in a direction inclined at an acute angle of at least against the perpendicular on said surface area; fixing in said channel an anchoring post means in such a position that an end portion thereof projects outwardly from said surface area; and attaching a tooth means to said outwardly projecting portion of said anchoring post means.

In another aspect of the invention it includes a fastening arrangement for attaching tooth means to a maxillary bone, comprising, in combination, a tooth member having a lower surface formed to fit the surface area of the maxillary bone where the tooth member is to be attached thereto and having a recess in said lower surface; at least one anchoring post means extending from said recess in a direction inclined at an acute angle of at least 15 against the perpendicular on said lower surface and anchored in the adjoining portion of the maxillary bone, an end portion of said anchoring post means projecting into said recess; and a mass of cement material filling said recess and surrounding said projecting portion of said anchoring post means so as to firmly fasten said tooth memher to said anchoring post means and thereby to said maxillary bone through said post means anchored therein.

In still another aspect of the invention it includes a dental anchoring post for attaching tooth means to a maxillary bone, comprising a straight rod portion adapted to be inserted into the bone and made of material chemically inert relative to the bone and to mucous tissues, said straight rod portion having a thickness of at least .3 mm. and up to 2.5 mm. so as to avoid dangerous contact with sensitive portions of the maxillary bone when inserted into the bone in a direction inclined at an acute angle of at least 5 with respect to the perpendicular on the top surface of said bone where the tooth means is to be located, and having an extension portion projecting outwardly when said rod portion is inserted into the bone and adapted to be firmly attached to the tooth means.

The fact that a dental anchoring rod according to the invention can be and is inserted into the bone in an inclined direction entails several advantages. First, the anchoring rod can be inserted to a comparatively great depth without any danger; second, it is possible to use for the attachment of one single tooth or of a support of a prosthesis one anchoring rod or a plurality thereof, e.g. with opposite inclinations, respectively, which assures a remarkable stability of the attachment irrespective of lateral or vertical forces which it has to withstand.

The straight rod portion of the dental post according to the invention may be made of alloys conventionally used in dental surgery as for instance a cobalt-chromium alloy known by the trade-name stellite.

The rod portion may also consist of a synthetic resin e.g. an acrylic resin, preferably without color, having sufficient mechanical strength the the purpose and being inert relative to the bone and to the mucous tissues.

However, it is also possible to make the rod portion of a metal which is coated at least partly or totally with such a resin in which case any metal for the metallic portion which has sufiicient mechanical strength may be used.

The rod portion or post may also be composed of a combination of two or more portions of which one or some is made of resin while one or the other of the remaining ones is made of metal. For example, a head portion made of resin may be attached to a rod portion of metal, or vice versa. However, preferably the rod portion or the post will be made in accordance with the invention of a wire of tantalum which is cold-rolled or drawn to the desired diameter. The drawing of such a wire should be carried out at low temperature in order to avoid oxidation and in order to improve by cold-working the mechanical qualities of the metal.

It should be noted that this cold-working can be carried out by reducing the diameter of a raw wire or blank from 10 mm. to 1 mm. so as to obtain a hardness of the order of 200 according to the Vickers scale and a tensil strength of kilogram per square millimeter.

As a matter of fact, tantalum is chemically inert relative to the bone material and when drawn as mentioned above has mechanical characteristics sufiicient to permit dental anchoring rods of small diameter according to the invention to resist not only to forces applied thereto when they are inserted into place, but also to be capable of resisting sufficiently lateral forces which the tooth attached by the post has to withstand.

The extension portion of the dental anchoring posts according to the invention projecting outwardly from the bone may be provided with a head which may be made of metal or may be a cap of any suitable material e.g. synthetic resin, platinum, etc.

The outer surfaces of the straight rod portion of the posts may be smooth but preferably they are rough or provided with fine grooves or channels or the like in order to provide for a better hold in the bone in view of the well known osteogenetic process according to which bone material will grow into such grooves or recesses as time goes on.

Accordingly, in line with the invention, the attachment of natural or artificial teeth or of dentures or the like is carried out by placing the dental anchoring posts into the maxillary bone at an inclination forming an acute angle with the perpendicular on the surface of the bone on which the particular tooth or prosthesis is to be supported. Preferably two or more of the posts are inserted in such a manner that the inclination of one post is opposite to or different from the inclination of the other or others and that the projecting extensions thereof are located adjacent to each other. It is always to be assumed that the artificial tooth or other member to be attached is provided with a recess of suflicient dimension for capping the above-mentioned outer extensions of the posts so that the final attachment can be carried out by filling the recess with some kind of cement which includes any type of sealing or solidifying material as for instance a dental synthetic resin which is self-polymerizing, or an oxyphosphate as conventionally used by dentists for fillings. After the recess mentioned above is filled with such material the tooth or the like is simply placed over the projecting outer end or ends of the post or posts, respectively. Hereby the posts are permanently fixed in their relatively inclined position so that it is quite impossible that they come loose or are pushed out.

For fixing the anchoring posts according to the invention in the bone one produces therein by means of a drilling device a channel of desired length or depth and of a diameter which should be slightly smaller than that of the selected post in its straight rod portion. For instance, the diameter of the channel may be .8 or .9 mm. for receiving a post the straight rod portion of which was a diameter of 1 mm. so that the post has to be introduced into the drilled channel with some force.

However, in a modification of the invention the straight rod portion of the post terminates in a drilling or cutting portion so that the post itself can be used as a drilling tool for producing the required channel for itself. Of course in this case the projecting extension portion of the post is formed as a head which is adapted to be gripped by the drilling device or a chuck thereof while nevertheless serving later as a anchoring portion for attaching the tooth or the like to the inserted post.

In other words, after the drilling operation is completed the head portion of the post is simply removed or released from the chuck or drilling device and the post remains embedded in the bone.

The novel features which are considered as characteristic for the invention are set forth in particular in the appended claims. The invention itself, however, both as to its construction and its method of operation, together with additional objects and advantages thereof, will be best understood from the following description of specific embodiments when read in connection with the accompanying drawings in which:

FIG. 1 is a diagrammatic cross-sectional elevation showing an artificial tooth attached to the lower maxillary bone by means of two dental anchoring posts according to the invention;

FIG. 2 is a similar View illustrating an attachment in which only one single dental anchoring post is used;

FIGS. 3-6 illustrate at an enlarged scale various suitable forms of anchoring posts according to the invention;

FIG. 7 illustrates in a manner similar to that shown by FIG. 1 the attachment of a dental prosthesis;

FIG. 8 is a diagrammatic sectional elevation illustrating the attachment of a loose tooth by means of a dental anchoring rod according to the invention introduced laterally;

FIG. 9 illustrates a particular form of a pair of dental anchoring rods according to the invention;

FIG. 10 is a perspective view of a dental anchoring rod according to the invention which in itself constitutes a drill;

FIG. 11 is an elevation of the post according to FIG. 10 showing how the latter is held in the chuck of a drilling device;

FIGS. 12 and 13 illustrate in a similar manner modifications of the device according to FIG. 10 as far as the head portion is concerned;

FIG. 14 is a partial perspective illustration of a further modification of the straight rod portion of a post according to the invention;

FIG. 15 is a diagrammatic sectional elevation illustrating the use of the dental anchoring posts according to the invention for attaching an artificial root and an artificial tooth to the bone; and

FIG. 16 illustrates in a manner similar to that of FIG. 1 the modification of the invention whereby a supporting plate is interposed between the tooth and the bone.

Referring now to FIGS. 1-9 it can be seen that the dental anchoring post according to the invention may be formed as a straight pin (FIG. 3) without a head portion, or with a suitable head portion (FIGS. 46). The individual posts 1 having preferably a pointed tip 2 for facilitating their insertion and a length so chosen that it is possible to insert them sufiiciently into the bone for obtaining a secure hold therein while still leaving an outwardly projecting extension portion on which then the tooth or the prosthesis can be attached. As a rule the straight rod portion which is to be inserted into the bone has in normal cases a length of 6 to 12 mm., but in certain cases it may have to be shorter, down to approximately 4 mm., or longer up to 30 mm. approximately. The projecting eX- tension portion has as a rule a length ranging between 2 and 5 mm., preferably however ranging between 3 and 4 mm. Consequently the overall length is preferably of the order of 12 to 15 mm. However, in view of the very small diameter of the straight rod portion according to the invention and stated the insertion of the post at an inclined angle makes it possible to avoid an undesirable penetration into the maxillary sinus or the dental canal so that the length of the post may be even up to 35 mm. if insertion thereof to a great depth is desired for any reason.

The thickness or diameter of the straight rod portion of the post may vary within reasonable limits depending upon the requirements. A thickness or diameter between .4 mm. and 2.5 mm. may be used, but preferably the thickness or diameter should be in the neighborhood of 1 mm. which dimension is satisfactory in most ordinary cases.

The dental anchoring rods according to the invention, or at least their straight rod portion which is to be inserted into the bone are preferably made of a metal which is chemically inert relative to the bone material or to the mucous tissues. Many metals or alloys suiting this condition are well-known. Many are designated by the gen eral name stellites. Generally they contain chromium, cobalt, and molybdenum, preferably in the following proportions: chromium 30%, cobalt 65% and molybdenum 5%.

However, in accordance with the invention, it is still preferred to make these posts or the portion thereof which is to be inserted into the bone of a drawn tantalum wire. Experiments of the inventor have shown that this metal which is also inert relative to the bone material makes it possible to manufacture the dental rods according to the invention without any difficulty. As a matter of fact, the tantalum which is a non-magnetic metal does not give rise to electric currents upon contact with the pH value of the saliva, of the bone or of the blood which value varies between individuals.

The posts according to the invention may be produced by casting or by drawing. The drawing method results in a greater strength even with the small thickness of the posts and therefore the posts made of drawn who can have a diameter or thickness smaller than that of those which are produced by casting.

As mentioned above the dental anchoring posts according to the invention may be without a head as shown in FIG. 3 or with a head as illustrated by way of example by FIGS. 4-6. As a rule the body or shank 1 is cylindrical. They may have a pointed tip 2 or may be blunt, or simply rounded at the end in order to facilitate their insertion. The outer surface of the shank may be smooth, or mat or provided with fine grooves, channels or the like so that a more solid connection with the surrounding bone material is obtained into which the post is inserted.

For inserting the dental anchoring rods according to FIGS. 1-9 into the bone one proceeds by drilling into the wall of the bone a channel which is inclined at an acute angle of at least relative to the axis of the tooth or of the prosthesis to be attached or in any case at an angle of inclination relative to the perpendicular on the surface where the tooth or the like is to be supported by the bone. Particularly if the thickness or diameter of the straight rod portion of the post is slightly below the diameter of the drilled hole an excellent fixation of the post in the bone is obtained in combination with the inclined direction of its insertion because under these circumstances the straight rod portion does not extend in the direction of the forces it has to withstand. On the other hand, because the thickness of the straight rod portion is small and only very slightly greater than the diameter of the drilled hole the bone itself is not subject to substantial pressures.

It is of particular advantage to use according to the invention for the attachment of one single tooth two or even more dental anchoring posts so arranged that the inclination of one is opposite to or different from that of the other or others, respectively. Such arrangements are illustrated for instance by FIGS. 1, 7, 9, and 16. Such an arrangement is particularly advisable if posts are used which do not have a distinct head portion of greater diameter or transverse dimension that the straight rod portion thereof Le. a post according to FIG. 3. It can be seen easily for instance from FIGS. 1 and 7 the opposite inclinations of the two straight rod portions I assure a very firm anchoring of the posts in the bone regardless of the direction of pushing or pulling forces which may act on the tooth or prosthesis held by the posts.

In all the illustrations of the drawings the tooth or prosthesis is indicated at T, the maxillary bone at 9, the

drilled channel at 3, the cavity or recess in the tooth is marked 5 and the cement or the like filling this recess is indicated at 6. The only exceptions are FIGS. 7, 8 and 16 which will be described further below. The head portions 10, it) and It? of FIGS. 4-6 Will also be described further below.

After the anchoring post or posts is or are inserted into the respective channel 3 the upper extension portion 4 of which rises above the upper bone surface some millimeters, the recess or cavity 5 of sufiicient dimension provided in the tooth T is filled with a cement e.g. a self-polymerizing synthetic resin 6 Whereafter the tooth or the like is placed with this cavity and with the cement over the projecting extension portion or portion 4. This results in a perfect fixation.

As is illustrated in FIG. 16 it is advantageous to place between the lower surface of the tooth T and the top surface of the bone 9 an insulating support plate which is made of a material chemically inert relative to the mucous tissue of the gum 9 and separates the cement 21 in. the cavity of the tooth T from the mucous tissue.

Consequently, with the protective plate 20 positioned as illustrated, any type of suitable cement material can be used without danger of irritation of the gums.

It should be understood that in FIGS. 1, 2, 7 and 16 the maxillary bone 9 has been illustrated in cross-section without showing therein any hollow portions like the alveolar recess ordinarily receiving the root of a tooth. This has been done without detracting from the essence of this invention because as a rule a dental prosthesis or an artificial tooth is not attached to the maxillary bone immediately after a tooth has been extracted. As is wellknown the bone grows within a certain time into the recess and closes the opening or recess which previously has accommodated the root of the extracted tooth.

Since the dental anchoring posts according to the invention are so constructed that they can be inserted into the maxillary bone at a certain angle of inclination, it is also possible to use these anchoring posts for consolidating loose teeth which nevertheless are still somehow supported in the maxillary bone. As illustrated by FIG. 8 one can proceed according to the invention in such a manner that first a recess 14- is hollowed out in the lateral wall of the tooth T whereafter starting from the recess 14 a channel 15 is drilled in inclined direction relative to the axis of the tooth T through the root portion of the tooth and beyond that into the maxillary bone 9. Of course, first the nerve of the tooth has to be killed or removed. Now a dental anchoring post 1 according to the invention can be driven through the channel 15 in the tooth and into the extension of this channel into the bone 9 whereby the tooth T is reliably fixed in the bone 9. The outer end portion of the post 1 projecting into the recess 14 is then surrounded by a cement filling in the usual manner.

It is to be noted that everything that has been stated above regarding the individual attachment of teeth as illustrated by FIGS. 1, 2, 8 and 16 applies analogously also for attaching dental prostheses. As is illustrated by PEG. 7 one can in this case attach to the maxillary bone 9, by means of a plurality of dental anchoring posts 1, as shown, according to the invention, any desired number of fixed support members 7 each of which is provided with a recess 8 similar to the recess 5 of FIGS. 1 and 2 and this recess may be filled with a suitable cement e.g. a dental self-polymerizing synthetic resin by means of which the support member '7 can be solidly connected with the upper ends 4 of the posts 1 and thereby to the maxillary bone 9. The actual prosthesis T can then be mounted on the supports 7 in the conventional manner.

As mentioned above the attachment of teeth or of prostheses as described above can be carried out not only with dental anchoring posts according to FIG. 3 but also with posts which are slightly different. This means that, instead of having a uniform diameter over its entire length, the post may terminate at its upper end in a portion which is transversely of an increased dimension as illustrated by FIGS. 4-6 and may be provided with grooves, beads or other irregularities so as to constitute a head portion which remains outside the bone when the straight rod portion of the post is inserted and serves for attaching thereto the tooth or prosthesis as illustrated by Way of example in FIG. 2.

It is further possible to arrange, as illustrated in FIGS. 2 and 4, the head portion at an angle relative to the straight rod portion of the post so that after insertion of the post in inclined direction the head has a substantialy vertical position. However in other cases as illustrated by FIGS. 5 and 6 the head portion may also be coaxial with the straight rod portion of the post.

Moreover, the head portion may be integral with the remainder of the post and made of the same material or metal as the latter (FIGS. 4 and 5) or, on the other hand, the head portion It) may be attached to the straight rod portion e.g. by a threaded connection, and

may in this case also be made of a different material e.g. of a dental type of synthetic resin.

Finally, the head portion may be provided with a perforation lt'la adapted to accommodate some of the cement material.

FIG. 9 illustrates a modication of the abovedescribed embodiments of the inventiOn consisting in a two-piece combination of two dental anchoring rods 1 and 11. As can be seen the post 1 which may or may not have a pointed tip 2 extends through an eye or perforation 13 of the other post 11 which may or may not have a pointed tip 12. In this manner a two-piece post combination is obtained wherein the two posts 1 and 11 are inclined relative to each other and each of them is, when the combination is mounted in the bone as described above inclined at an acute angle relative to the perpendicular on the surface where the artificial tooth or the like meets with the top surface of the maxillary bone. As can be seen, the post 1 will be placed in position after the post 11 has been inserted whereafter they constitute together a combined mechanically joined structure.

In all the above described cases it is necessary to drill, before the insertion of the posts according to the invention, a channel into which afterwards the posts are to be inserted. However, in the modifications of the invention as described further below the dental anchoring post according to the invention constitutes itself a drill which evidently constitutes a substantial facilitation of the insertion of the posts and also reduces any possible discomfort of the patient.

FIGS. 10 and 11 illustrate one example of such a modified form of the dental anchoring posts according to the invention. It can be seen that in this case the straight rod portion 1a of the post terminates in a cutting edge 2b and is'formed at 2a like a helical drill with one or more cutting grooves 3a.

The other end or extension portion of the post is formed as a head 4a which is adapted to be received by a corresponding slot or recess 7a of the chuck 6a of a drilling device of any conventional type as normally used by a dentist.

Before the drilling device is put into operation the post 1a is pushed in direction of the arrow f with its head 14a into the slot 7a so as to insure the proper transmission of torque from the drill chuck 6a to the post 1a. The post In is now used like an ordinary dental drill for drilling the required channel into the bone as described above. As soon as the post 10 has been moved a sufficient distance into the bone the drilling operation is stopped, the chuck 6a is removed from the post la by pulling it away in the direction of the arrow f and the post 1a is simply left in the channel it has produced. The projecting head portion 4!: can now be used for attaching the tooth or the like in the same manner as described above in relation to FIGS. 1, 2, 7, or 16-. In order to insure a better connection between the cement and the head portion 4a the latter may be provided with transverse recesses a into which the cement will enter.

FIG. 12 illustrates a further modification of the drilltype post In according to FIGS. and 11. In this case the shank 1a" otherwise similar to the shank 1a described above is provided with a head portion 4a which has cross-shape with arms extending transversely of the axis of the shank la. This form is advisable if the chuck of the drilling device has jaws conforming to the crossshape of the head 4a so as to insure a firm and reliable grip between the chuck and the head of the post.

The example according to FIG. 13 constitutes still another modification in which case the head portion 4a" is provided with a thread portion 8a which is adapted to engage a correspondingly provided internal thread in the chuck 6a of the drilling device. In this case, after the drilling operation is completed the chuck of the drilling device is simply unscrewed from the post In" and again the post is then left firmly embedded in the bone.

8 Both in the cases of FIGS. 12 and 13 the formation of the head portions 4a and 4a" assure an excellent ongagement of the head with the cement.

As mentioned above the straight rod portion of the dental anchoring post according to the invention need not be necessarily cylindrical. For instance, FIG. 14 illustrates a portion of the shank 1b of a post according to the invention and it can be seen that in this case the shank 1b is not cylindrical but is a prismatic member having cutting edges along its length or at least at its tip as illustrated at If).

The dental anchoring posts according to the invention are adapted to be used in many different cases of dental Work. For example, in view of the minute diameter of thickness of the posts according to the invention and in view of the position thereof at an angle of inclination relative to the perpendicular on the support surface of the bone or of the artificial tooth it is also possible to mount an artificial tooth T on an artificial root 18 as illustrated by FIG. 15. The artificiaLroot 18 may be made of synthetic material, or if desired of tantalum or stellite (but in this case with prefabricated channels therethrough for receiving the dental posts 16 and 17) and may be placed as illustrated into the root socket of the jawbone 19 after the original root of the respective natural tooth has been extracted. For attaching not only the artificial root 18 to the bone 19 but also for providing an attachment for the artificial tooth T to the root 18, the procedure is analogous to the one described above. Channels are drilled at the inclination required either through the resin material of the artificial root 18 and then into the bone 19 or, in the other case, through the prefabricated holes of a metal root 18 into the bone 19 whereafter the dental anchoring posts 16 and 17 are placed into the channels or left therein as described above, and now by means of cement 6 in the cavity 5 of the tooth T the latter is attached to the projecting upper ends of the posts 16 and 17. Of course, it makes no difference whether the tooth T in FIG. 15 is a portion of a natural tooth or an artificial tooth or cap or crown made of synthetic resin, ceramic or any other material.

It will be understood that each of the elements described above, or two or more together, may also find a useful application in other types of method and means for attaching teeth and the like to a maxillary bone differing from the types described above.

While the invention has been illustrated and described as embodied in a method and means of attaching teeth or the like with the aid of anchoring posts to a maxillary bone it is not intended to be limited to the details shown, since various modifications and structural changes may be made without departing in any way from the spirit of the present invention.

Without further analysis, the foregoing will so fully reveal the gist of the present invention that others can by applying current knowledge readily adapt it for various applications without omitting features that, from the standpoint of prior art, fairly constitute essential characteristics of the generic or specific aspects of this invention and, therefore,'such adaptations should and are intended to be comprehended within the meaning and range of equivalence of the following claims.

What is claimed as new and desired to be secured by Letters Patent is:

1. A method of attaching discrete tooth means with the aid of anchoring post means to a maxillary bone, comprising the steps of: drilling substantially from the center of the surface area of the discrete maxillary bone where the tooth means is to be attached at least two channels of predetermined diameter into the maxillary bone in diverging directions inclined at an acute angle of at least 5 against the perpendicular on said surface area; fixing in each of said channels an anchoring post means, respectively, in such a position that an end portion thereof projects outwardly from said surface area; and attaching a discrete tooth means to said outwardly projecting portions of said anchoring post means.

2. A method of attaching a loose tooth with the aid of anchoring post means to a maxillary bone, comprising the steps of: producing a recess in a side surface of the loose tooth portion projecting from the maxillary bone and drilling from said recesses through the root of the tooth and into the maxillary bone at least one channel of predetermined diameter, which channel passes through the root in a position of other-than alignment with the root canal and which is inclined at an acute angle of at least against the axis of the tooth, fixing in said channel an anchoring post means in such a position that an end portion thereof projects outwardly into said recess and attaching said tooth to said outwardly projecting portion of said anchoring post means by filling said recess with cement material surrounding said projecting portion of said anchoring post means.

3-. A method of attaching tooth means with the aid of an artificial root and of anchoring post means to a maxillary bone, comprising the steps of: placing an artificial root of a material inert relative to bone and mucous tissues into alveolar recess of the maxillary bone; drilling substantially from the center of the surface area of said artificial root where the tooth means is to be attached at least one channel of predetermined diameter into the maxillary bone in a direction inclined at an acute angle of at least 5 against the perpendicular on said surface area; fixing in said channel an anchoring post means in such a position that one end portion thereof is anchored in the maxillary bone an another end portion projects outwardly from said surface area; and attaching a tooth ments to said outwardly projecting portion of said anchoring post means.

4. A method of attaching a tooth means with the aid of anchoring post means to a maxillary bone, comprising the steps of: drilling with a drilling tool substantially from the center of the surface area of the maxillary bone where the tooth means is to be attached at least one channel of predetermined diameter into the maxillary bone in a direction inclined at an acute angle of at least 5 against perpendicular on said surface area; leaving said drililng tool in said channel in such a position that an end portion thereof projects outwardly from said surface area; and attaching a tooth means to said outwardly projecting portion of said drilling tool.

5. A set of dental anchoring posts for attaching tooth means to a maxillary bone, each post comprising a straight rod portion adapted to be inserted into the bone and made of material chemically inert relative to the bone and to mucous tissues, said straight rod portion having a thickness of at least .3 mm. and up to 2.5 mm. so as to avoid dangerous contact with sensitive portions of the maxillary bone when inserted into the bone in a direction inclined at an acute angle of at least 5 with respect to the perpendicular on the top surface of said bone where the tooth means is to be located, and having an extension portion projecting outwardly when said rod portion is inserted into the bone and adapted to be firmly attached to the tooth means, the extension portion of one of said posts having a perforation, and the extension portion of the other most extruding through said performation so that said straight rod portions of the two posts form an acute angle between each other. and are hraced one against the other to increase their stability against forces acting on the tooth means.

6. A dental anchoring post as claimed in claim 5, wherein said head portion is formed as a flat plate mem ber extending transversely of the post.

7. A dental anchoring post as claimed in claim 5, wherein said head portion is provided with at least one clamping recess.

8. A dental anchoring post as claimed in claim 5, wherein said head portion is shaped in crossorm with arms extending transversely of said rod portion.

9. A dental anchoring post as claimed in claim 5, wherein said head portion is provided with a threaded part adapted to be screwed into a drilling device.

10. A method as claimed in claim 3 wherein said artificial root is provided with prefabricated channels through which a drilling tool is guided before and while producing said channel in the maxillary bone and through which said anchoring post means are inserted into said channel for anchoring in the maxillary bone.

11. A dental anchoring post for attaching tooth means to a maxillary bone, comprising a substantially cylindrical straight rod portion adapted to be inserted into the bone and having a free end terminating in at least one cutting edge adapted to act as a drill bit, said rod portion being made from material chemically inert relative to the bone and to mucous tissues but hard enough to enable said cutting edge to drill a bore into the bone when said rod portion is rota-ted, said straight rod portion being formed with at least one helical groove for facilitating firm anchoring of said rod portion in the bone and having a thickness of at least .3 millimeters and up to 2.5 millimeters so as to avoid dangerous contact with sensitive portions of the maxillary bone when inserted into the bone in a direction inclined at an acute angle of at least 5 degrees with respect to the perpendicular on the top surface of said bone Where the tooth means is to be located, said anchoring post further comprising an extension portion projecting outwardly when said rod portion is inserted into the bone, and a head portion at the outwardly projecting end of said extension portion and being adapted to be gripped by a chuck of a drilling machine so that the post itself can serve as a drill for cutting a channel in the bone into which it is to be inserted, said head portion further facilitating gripping of said anchoring post and inserting of the same into the bone and be ing adapted to be firmly attached to the tooth means.

12. A dental anchoring post for attaching tooth means to a maxillary bone, comprising a rod portion adapted to be inserted into the bone and having a free end terminating in at least one cutting edge adapted to act as a drill bit, said rod portion being made from material chemically inert relative to the bone and to mucous tissues but hard enough to enable said cutting edge to drill a bore into the bone when said rod portion is rotated, said anchoring post further comprising an extension por-tion projecting outwardly when said rod'portion is inserted into the bone, and a head portion at the outwardly projecting end of said extension portion and being adapted to be gripped by a chuck of a drilling machine so that the post itself can serve as a drill for cutting a channel in the bone into which it is to be inserted.

13. A method as defined in claim 4; and further comprising the steps of drilling with an additional drilling tool substantially from the center of the surface of the maxillary bone an additional channel of predetermined diameter in a direction diverging from said one channel and inclined at an acute angle of at least 5 against the perpendicular on said surface area; leaving said additional tool in said additional channel in such a position that an end portion thereof projects outwardly from said surface area; and attaching said tooth means also to the outwardly projecting end portion of said additional drilling tool.

14. A dental anchoring post for attaching tooth means to a maxillary bone, comprising a substantially cylindrical straight rod portion adapted to be inserted into the bone and having a free end terminating in at least one cutting edge adapted to act as a drill bit, said rod portion being made from material chemically inert relative to the bone and to mucous tissues but hard enough to enable said cutting edge to drill a bore into the bone when said rod portion is rotated, said straight rod portion having a thickness of at least .3 millimeter and up to 2.5 millimeters so as to avoid dangerous contact with sensitive portions of the maxillary bone when inserted into the bone in a direction inclined at an acute angle of at least 5 degrees with respect to the perpendicular on the top surface of said bone where the tooth means is to be located, said anchoring post further comprising an extension portion projecting outwardly when said rod portion is inserted into the bone, and a head portion at the outwardly projecting end of said extension portion and being adapted to be gripped by a chuck of a drilling machine so that the post itself can serve as a drill for cutting a channel in the bone into which it is to be inserted, said head portion further facilitating gripping of said anchoring post and inserting of the same into the bone and being adapted to be firmly attached to the tooth means.

15. A method of attaching tooth means to a maxillary bone, comprising the steps of drilling substantially from the center of the surface area of the maxillary bone where the tooth means is to be attached at least one channelrof predetermined diameter into the maxillary bone in a direction inclined at an acute angle of at least against the perpendicular on said surface area; fixing in said channel an anchoring post means in such a position that an end portion thereof projects outwardly from said surface area; providing a tooth means having in a surface thereof which is to be juxtaposed with said surface area a cavity adapted to receive said outwardly projecting portion of said anchoring post means and to further receive a body of hardenable material for anchoring said portion in said cavity; interposing a protective support plate of a material inert relative to said maxillary bone and to mucous tissue, between said surface and said surface area; and attaching said tooth means to said outwardly projecting portion of said anchoring post means by placing said tooth means over said portion so that the latter is received in said cavity containing said body of material, and so that said support plate closes said cavity and prevents contact of the contents thereof with said maxillary bone.

16. A dental anchoring post for attaching tooth means to a maxillary bone, comprising a substantially cylindrical straight rod portion adapted to be inserted into the bone and having a free end terminating in at least one cutting edge adapted to act as a drill bit, said rod portion being made from a material consisting at least in part of tantalum and chemically inert relative to the bone and to mucous tissues but hard enough to enable said cutting edge to drill a bore into the bone when said rod portion is rotated, said straight rod portion having a thickness of at least .3 millimeter and up to 2.5 millimeters so as to avoid dangerous contact with sensitive portions of the maxillary bone when inserted into the bone in a direction inclined at an acute angle of at least 5 degrees With respect to the perpendicular on the top surface of said bone where the tooth means is to be located, said anchoring post further comprising an extension portion projecting outwardly when said rod portion is inserted into the bone, and a head portion at the outwardly projecting end of said extension portion and being adapted to be gripped by a chuck of a drilling machine so that the post itself can serve as a drill for cutting a channel in the bone into which it is to be inserted, said head portion further facilitating gripping of said anchoring post and inserting of the same into the bone and being adapted to be firmly attached to the tooth means.

References Cited UNITED STATES PATENTS 276,920 5/1883 Starr 32-10 616,302 12/1898 Evans 3213 2,609,604 9/1952 Sprague 321 238,334 3/1881 Bonwill 3213 342,271 5/1886 Starr 32-13 FOREIGN PATENTS 1,128,217 8/1956 France. 441,519 11/1948 Italy.

OTHER REFERENCES Pallus, W. S., et al.: Surgical Procedure for Lower Implant Dentures, Dental Digest, February 1953; pp. 56-61.

LOUIS G. MANCENE, Primary Examiner. R. E. MORGAN, Examiner.

C. R. WENTZEL, Assistant Examiner. 

2. A METHOD OF ATTACHING A LOOSE TOOTH WITH THE AID OF ANCHORING POST MEANS TO A MAXILLARY BONE, COMPRISING THE STEPS OF: PRODUCING A RECESS IN A SIDE SURFACE OF THE LOOSE TOOTH PORTION PROJECTING FROM THE MAXILLARY BONE AND DRILLING FROM SAID RECESSES THROUGH THE ROOT OF THE TOOTH AND INTO THE MAXILLARY BONE AT LEAST ONE CHANNEL OF PREDETERMINED DIAMETER, WHICH CHANNEL PASSES THROUGH THE ROOT IN A POSITION OF OTHER-THAN ALIGNMENT WITH THE ROOT CANAL AND WHICH IS INCLINED AT AN ACUTE ANGLE OF AT LEAST 5* AGAINST THE AXIS OF THE TOOTH, FIXING IN SAID CHANNEL AN ANCHORING POST MEANS IN SUCH A POSITION THAT AN END PORTION THEREOF PROJECTS OUTWARDLY INTO SAID RECESS AND ATTACHING SAID TOOTH TO SAID OUTWARDLY PROJECTING PORTION OF SAID ANCHORING POST MEANS BY FILLING SAID RECESS WITH CEMENT MATERIAL SURROUNDING SAID PROJECTING PORTION OF SAID ANCHORING POST MEANS. 